A reeling Celtics team had quite the swing of emotions on Sunday afternoon, starting with the devastating news that point guard Rajon Rondo will miss the remainder of the season with a torn ACL. Very little on the court could possibly compete with that huge loss, but a 100-98 double overtime win against the rival Miami Heat in Ray Allen’s return to Boston is about as good as it gets.

Paul Pierce had a triple double and came through in the clutch, nailing the go-ahead basket with about a half a minute remaining in the second overtime period. The team also had key contributions from Kevin Garnett, who led the team with 24 points, and Jeff Green, who played 42 minutes off the bench.

LeBron James scored a game-high 34 points on 14-for-31 shooting to lead the Heat, including the game-tying three-pointer with seven seconds remaining in regulation. Dwyane Wade and Chris Bosh chipped in 17 and 16 points, respectively.

The game notably included the return of former Celtics shooting guard Ray Allen, who was impressive in 38 minutes off the bench. Allen shot 7-of-17 from the field for 21 points, his highest scoring total since early November. In two games this year against the Celtics, who Allen left for a smaller contract in Miami, he has scored a total of 40 points.

The win would normally be seen as an instant momentum builder heading into the last 38 games of the year, with Boston currently holding a 2.5 game lead over the Philadelphia 76ers for the final spot in the Eastern Conference playoffs. Yet the loss of Rondo nearly ensures upcoming struggles, and in fact his injury could lead to moves made by the front office in an attempt to plan for next year.

Despite arguably the best win of the year, today will be most remembered for the worst news of the season for the Celtics. The Celtics will attempt to regroup for their next game on Jan. 30 at the TD Garden against the Sacramento Kings.